SCM Full Form in Medical term is Sternocleidomastoid Muscle. It is one of the most superficial and largest cervical muscles. It plays an important role in rotating the head in the opposite direction, thereby flexing the neck. The accessory nerve innervates the SCM.
When both sides of the muscle work together, it flexes the neck and extends the head. If only one side fully functions, it turns the head in the opposite direction and laterally on the same side. It also works as a respiration muscle along with the neck’s skull muscles.
The SCM is innervated by two heads – a lateral fleshy clavicle head and a medial round and tendon sterna head. They develop from the anterolateral base of the manubrium sterni and the medial third of the upper surface of the clavicle, respectively. The thickness of CH is different.
Once the SCM is damaged, you may experience pain in your forehead, sinuses, or near your eyebrows. Feelings of pressure or tightness may accompany aching, dull aches. More severe symptoms may include bruising, redness, and swelling.